I recently acquired a pallet of Olde Castle retaining wall blocks for about $1/each. I didn't have a plan for them at the time, I just jumped prematurely because of the price mistake. Now I want to use them for a 15' curved 20" tall retaining wall on a slope, the problem is, I don't exactly trust them for retaining wall usage. According to the Lowes website, they are rated for small retaining wall usage (Shop Oldcastle 12"L Tan/Charcoal Olde Manor Wall at Lowes.com) Once the blocks were delivered I realized there was no lip that is typical with most retaining wall blocks, and that these weighed about half of what normal blocks of there size weigh(only about 30lbs a block compared to 75lbs for a like sized block from reputable block co).

Lowes says these are rated for small retaining walls, but I have my doubts due to weight and lack of a 'locking lip'. Has anyone used these with success for anything more than a raised flower bed? I don't want a tall retaining wall, 20" at most. I just don't want a heavy rain to shift the wall. Should I use mortar, adhesive, rebar, or something else to strengthen the bond and create a stronger wall? I am at a loss as to what to do with this. My only other option seems to be going with a reputable retaining wall block company.

Oldcastle (a huge Irish internationally known company) makes many different types of retaining wall, mostly on license from one of the major product developers and licensors. They will supply what a retailer wants to buy and have no control over the expect for specific products. Oldcastle is the largest manufacturer of hardscape concrete products and concrete products in the U.S. and make many different systems of block, depending on the plant location. I have seen Oldcastle retaining wall block used on 20' high walls a mile or so long by a DOT.

The units you bought were a low end generic unit for "many applications" according to the sketchy Lowe's information and specifications. Mortar is not required, but may be necessary for some uses, depending where you are.

As you correctly noted, there were no shear lugs or provision for pricey pins, so the height is limited since they are for a low landscape wall where lateral shear forces are minimal. The Lowe's product information is severely limited.

I suppose my original post came off a bit negative on the company as a whole, this was meant towards the model of the block, not the reputation of the company. I've seen good things come from Olde Castle, this block unfortunately is not what I would consider a good thing from a retaining perspective. For ornamental usage and raised beds, they would be great and would be a good value.

It sounds like I'm better off cutting my losses on these particular blocks and getting blocks more suited for small retaining wall purposes? It seems like more work would have to be done to make these work for me than is worth it.